Introduction and Context
Chordoma is a rare, locally aggressive malignant bone tumor that arises from notochordal remnants and most commonly affects the skull base (clivus), mobile spine, and sacrum. Although slow-growing, chordomas frequently recur locally and ultimately metastasize in a substantial fraction of patients, producing long‑term morbidity. Because chordomas are uncommon and anatomically complex, randomized trial evidence is very limited; management has historically relied on multidisciplinary best practices and retrospective series.
In July 2025 the Global Chordoma Consensus Group (an international multidisciplinary panel including surgeons, radiation oncologists, pathologists, medical oncologists, radiologists, rehabilitation and palliative care specialists, and patient representatives) met in Milan to update the 2015 international consensus. The results were published in JAMA Oncology (Radaelli et al., 2026). The 2026 consensus updates recommendations on diagnosis, pathology, surgery, radiotherapy, systemic therapy, follow-up, and supportive care for pediatric and adult patients with primary, localized chordoma.
Why this update matters now
– Advances since 2015: improved imaging and surgical navigation, wider adoption of high‑dose conformal radiotherapy including proton and carbon‑ion therapy, deeper pathologic understanding (WHO classification refinements and the role of brachyury), and expanding early-phase systemic trials.
– Persistent challenges: rarity of disease, site-specific surgical complexity, late recurrences (often many years later), and sparse randomized evidence.
The 2026 consensus aims to harmonize practice across centers, support shared decision‑making, and identify research priorities.
New Guideline Highlights
Major themes and top takeaways
– Central principle: care at experienced, multidisciplinary centers with expertise in chordoma, where imaging, pathology, surgery, radiotherapy, and supportive services are integrated.
– Primary treatment strategy: maximally safe resection followed by high‑dose, highly conformal radiotherapy in virtually all patients with localized disease.
– Anatomy‑stratified recommendations: explicit, separate guidance for skull base (clival), mobile spine, and sacral lesions, recognizing different surgical strategies, neurologic risks, and radiotherapy constraints.
– Pathology and molecular testing: routine use of brachyury (T) immunohistochemistry to confirm diagnosis and recognition of poorly differentiated chordoma as a distinct entity requiring pediatric‑specific considerations.
– Systemic therapy: remains largely investigational in the primary localized setting; systemic agents are generally reserved for unresectable, recurrent, or metastatic disease or within clinical trials. Immunotherapy and targeted agents (eg, inhibitors targeting PD-1/PD-L1, EGFR, or other pathways) are under evaluation.
– Long‑term follow‑up: risk‑adapted, life‑long surveillance is recommended due to late recurrences; follow-up protocols are specified by tumor site and recurrence risk.
Key practical messages for clinicians
– Refer newly diagnosed cases to a high‑volume, multidisciplinary center early.
– Plan surgery with preoperative radiotherapy discussions to optimize timing and minimize morbidity.
– Use high‑dose conformal radiotherapy (proton, carbon ion, or stereotactic techniques as appropriate) after surgery in most cases; definitive radiotherapy is an option for unresectable tumors.
– Engage rehabilitation, pain management, and psychosocial support teams from the start.
Updated Recommendations and Key Changes from 2015
What’s new or changed (high‑level)
– Stronger emphasis on centralizing care: the 2026 statement formalizes referral to multidisciplinary centers as a foundational recommendation.
– Stratification by anatomical site: the 2026 consensus expands site‑specific technical guidance (skull base vs mobile spine vs sacrum) including surgical corridors and radiotherapy planning constraints.
– Radiotherapy advances: clearer endorsement of high‑dose proton and carbon‑ion therapy and stereotactic approaches when anatomically feasible, with guidance on target delineation and dose recommendations.
– Pathology and molecular diagnostics: routine brachyury immunohistochemistry is recommended; recognition of poorly differentiated chordoma (often SMARCB1/INI1 deficient) has management and prognostic implications, especially in children.
– Pediatric-specific guidance: the update expands pediatric recommendations and addresses age‑related considerations for radiotherapy modality and long‑term functional outcomes.
– Follow-up: more prescriptive, risk‑adapted long‑term surveillance intervals (years to decades) and recommended imaging modalities.
Summary table: Selected updates (2015 → 2026)
– 2015: General multidisciplinary recommendation; surgery + radiotherapy favored. 2026: Stronger mandate for treatment at expert centers; anatomy‑specific pathways.
– 2015: Radiotherapy recommended but modality not prescriptive. 2026: Explicit support for high‑dose proton/carbon ion therapy and stereotactic radiotherapy with dosing guidance.
– 2015: Pathology diagnosis based on morphology and IHC. 2026: Routine brachyury IHC and recognition of poorly differentiated variant; molecular testing recommended when available.
– 2015: Limited pediatric content. 2026: Expanded pediatric recommendations and attention to long‑term survivorship.
(hereafter the article uses the evidence-grade framework applied by the consensus group; the panel assigned levels of evidence and grades to recommendations based on published data and expert opinion.)
Topic-by-Topic Recommendations
Diagnosis and staging
– Imaging: MRI with contrast is the imaging modality of choice for local extent; CT is required for bone anatomy and surgical planning. Preoperative whole‑body staging (CT chest ± PET/CT) is recommended to exclude metastatic disease.
– Biopsy: image‑guided core needle biopsy is recommended when the diagnosis is uncertain and when biopsy will change management. For skull base lesions, transnasal endoscopic biopsy may be considered by experienced teams. Avoid incisions or approaches that would complicate future en bloc resection unless unavoidable.
– Pathology: diagnosis should include morphology and brachyury (T) immunohistochemistry (positive in conventional chordoma). Consider additional testing (SMARCB1/INI1 status) to identify poorly differentiated chordoma, particularly in children.
Surgery
– Overarching goal: maximally safe resection balancing oncologic control with preservation of neurological, genitourinary, and gastrointestinal function.
– Site‑specific surgical approach:
– Skull base (clival): endoscopic endonasal approaches are preferred when feasible; the aim is gross total resection when safe, recognizing that neural and vascular anatomy often limit radical excision.
– Mobile spine: en bloc resection with negative margins is the ideal when technically feasible and when morbidity is acceptable; staged approaches and combined anterior‑posterior strategies are discussed in detail.
– Sacrum: low sacral (below S2) tumors may be amenable to wide resection with acceptable functional outcome; high sacral resections (S1–S2) risk major neurologic compromise and require individualized planning and comprehensive counseling.
– Margin reporting: surgical reports should clearly document margin status and intraoperative considerations. When margin‑negative resection cannot safely be achieved, plan for postoperative high‑dose radiotherapy.
Radiotherapy
– Guiding principle: postoperative high‑dose, highly conformal radiotherapy is recommended in most patients (adjuvant RT after surgery) to reduce local recurrence.
– Modality recommendations:
– Photon stereotactic radiosurgery (SRS) or stereotactic body radiotherapy (SBRT) can be used for small skull base or spinal residues when organs at risk permit.
– Proton therapy is recommended in many centers as the primary high‑dose modality because of favorable dose distribution when organs at risk (brainstem, spinal cord) limit photon dose.
– Carbon‑ion radiotherapy is endorsed particularly where higher relative biological effectiveness (RBE) is desirable (for large tumors or radioresistant histologies) and where available.
– Dose guidance: the panel provided modality‑specific dose ranges and target delineation principles to achieve tumor control while respecting normal‑tissue constraints (doses are detailed in the consensus document). The general recommendation is to deliver the highest safe biologically effective dose compatible with neighboring critical structures.
– Definitive RT: for unresectable tumors or patients unfit for surgery, definitive high‑dose conformal RT (proton or carbon ion where available) is a recommended approach.
Systemic therapy and clinical trials
– Systemic therapy is not recommended routinely in the primary localized setting outside clinical trials.
– For unresectable, recurrent, or metastatic chordoma, targeted agents (eg, inhibitors of PDGFR, EGFR, or other pathways) and immunotherapies are options in clinical trials and select cases; imatinib has shown disease control in some case series for PDGFR‑positive tumors.
– The consensus encourages enrollment in well‑designed prospective clinical trials and biological translational studies, and supports molecular profiling where feasible to inform trial eligibility.
Follow‑up and survivorship
– Life‑long, risk‑adapted surveillance is recommended because recurrences can occur many years after treatment.
– Typical schedule (site‑adapted) – examples:
– Years 0–5: clinical exam and MRI (local site) every 3–6 months for the first 2 years, then every 6–12 months.
– Years 5–10: clinical exam and MRI every 6–12 months.
– After 10 years: annual clinical review with MRI every 1–2 years or individualized based on risk factors.
– Imaging for metastasis (eg, chest CT) should be obtained periodically, with frequency guided by initial risk features.
– Survivorship care should address functional deficits, bowel/ bladder dysfunction (especially sacral cases), sexual dysfunction, chronic pain, secondary effects of radiotherapy, and psychosocial support.
Special populations
– Pediatrics: recognize the distinct biology of some pediatric chordomas (including poorly differentiated chordoma). Radiotherapy modality and dose must balance tumor control with long‑term toxicity; proton or heavy‑ion therapy is favored to reduce late effects when available. Pediatric patients should be treated in centers with pediatric oncology expertise.
– Elderly or frail patients: individualized approach balancing quality of life and symptom control; definitive radiotherapy may be prioritized over morbid surgery in some cases.
Expert Commentary and Insights
Consensus group perspectives
– Importance of centralization: the panel emphasized that outcomes are substantially better at high‑volume multidisciplinary centers, both in terms of local control and management of treatment‑related morbidity.
– Surgery + high‑dose RT remains the cornerstone: despite advances in RT, the panel could not replace surgery as a primary modality in resectable cases; instead, multimodality care remains standard.
– Radiotherapy technology matters: many panel members underscored that access to proton or carbon‑ion therapy can materially influence planning and outcomes, particularly for skull base tumors abutting critical neural structures.
Controversies and areas without consensus
– Optimal radiotherapy modality: while the consensus endorses proton and carbon ion therapy when available, the superiority of one modality over another for every clinical scenario remains unproven in randomized studies.
– Role and timing of neoadjuvant radiotherapy: limited evidence and divergent expert opinion mean neoadjuvant RT is reserved for selected cases and trials.
– Systemic treatments: the field lacks high‑quality evidence of routine systemic therapy benefit in localized disease; many experts call for collaborative trials and biomarker‑driven studies.
Research priorities highlighted by the group
– Prospective, collaborative trials of radiotherapy modalities, dose escalation, and integration with surgery.
– Translational research into chordoma biology (brachyury, molecular subtypes) to identify therapeutic targets.
– Longitudinal survivorship studies to characterize functional outcomes and late toxicities.
– Pediatric‑specific trials and registries.
Practical Implications
For clinicians
– Early referral to multidisciplinary centers and preoperative multidisciplinary planning are essential.
– When surgery will be performed, coordinate with radiation oncologists to plan postoperative radiotherapy and to minimize wound complications.
– Use brachyury immunohistochemistry routinely for diagnostic confirmation; consider molecular testing for trial enrollment.
For health systems
– Investment in regional centers of excellence for chordoma care, including access to advanced radiotherapy modalities (proton/carbon ion) or referral pathways to centers that provide them, will likely improve outcomes.
Patient communication and shared decision‑making
– Discuss realistic goals: local tumor control, functional preservation, and the potential need for long‑term surveillance.
– Explain that while systemic options are limited in the primary localized setting, clinical trials may offer access to novel therapies.
Example vignette
John Smith, a 52‑year‑old man, presents with low back pain radiating to the posterior thigh. MRI shows a large S2–S4 sacral mass consistent with chordoma. After CT chest to exclude metastases and image‑guided biopsy confirming brachyury‑positive chordoma, John is referred to a multidisciplinary chordoma center. The team counsels him that an en bloc sacrectomy extending to S3 offers the best chance for local control but may cause bowel and bladder dysfunction. After a shared decision process, they plan a staged posterior approach aiming for maximal safe resection, followed by postoperative proton therapy to a high dose to the tumor bed. Early involvement of physiotherapy, stoma counseling, and pain management are arranged. Long‑term surveillance is scheduled with MRI every 6 months for 2 years, then annually thereafter.
References
1) Radaelli S, Frezza AM, Fossati P, et al; Global Chordoma Consensus Group. Global Consensus on the Management of Primary Localized Chordoma. JAMA Oncol. 2026 Jul 9. PMID: 42424068. https://pubmed.ncbi.nlm.nih.gov/42424068/
2) WHO Classification of Tumours Editorial Board. WHO Classification of Tumours: Soft Tissue and Bone Tumours. 5th ed. Lyon: IARC; 2020. (Defines chordoma subtypes and diagnostic criteria, including brachyury use.)
3) The Chordoma Foundation. Clinical resources and patient guidance. https://www.chordomafoundation.org/ (advocacy, registries, and information about centers of excellence and clinical trials).
(For full technical details, modality‑specific dose constraints, and the panel’s evidence grades, readers should consult the full JAMA Oncology consensus document cited above.)
Closing note
The 2026 Global Chordoma Consensus represents a practical, multidisciplinary update that codifies current best practices and highlights where evidence is lacking. For clinicians, the key actionable points are early referral to experienced teams, a default multimodality strategy of maximally safe surgery plus high‑dose conformal radiotherapy, routine diagnostic use of brachyury immunostaining, and life‑long, risk‑adapted surveillance. For researchers and funders, the consensus identifies clear priorities—comparative radiotherapy studies, translational biology, and collaborative trials—to improve long‑term outcomes in this rare but challenging disease.
